Diabetes and obesity (sometimes collectively referred to as “diabesity”) are interrelated in that obesity is known to exacerbate the pathology of diabetes and greater than 60% of diabetics are obese. Most human obesity is associated with insulin resistance and leptin resistance. In fact, it has been suggested that obesity may have an even greater impact on insulin action than diabetes itself (Sindelka et al., Physiol Res., 2002, 51, 85-91). Additionally, several compounds on the market for the treatment of diabetes are known to induce weight gain, a very undesirable side effect to the treatment of this disease.
Cardiovascular disease is also interrelated to obesity and diabetes. Cardiovascular disease encompasses a wide variety of etiologies and has an equally wide variety of causative agents and interrelated players. Many causative agents contribute to symptoms such as elevated plasma levels of cholesterol, including non-high density lipoprotein cholesterol (non-HDL-C), as well as other lipid-related disorders. Such lipid-related disorders, generally referred to as dyslipidemia, include hyperlipidemia, hypercholesterolemia and hypertriglyceridemia among other indications. Elevated non-HDL cholesterol is associated with atherogenesis and its sequelae, including cardiovascular diseases such as arteriosclerosis, coronary artery disease, myocardial infarction, ischemic stroke, and other forms of heart disease. These rank as the most prevalent types of illnesses in industrialized countries. Indeed, an estimated 12 million people in the United States suffer with coronary artery disease and about 36 million require treatment for elevated cholesterol levels.
Epidemiological and experimental evidence has shown that high levels of circulating triglyceride (TG) can contribute to cardiovascular disease and a myriad of metabolic disorders (Valdivielso et al., 2009, Atherosclerosis Zhang et al., 2008, Circ Res. 1; 102(2):250-6). TG derived from either exogenous or endogenous sources is incorporated and secreted in chylomicrons from the intestine or in very low density lipoproteins (VLDL) from the liver. Once in circulation, TG is hydrolyzed by lipoprotein lipase (LpL) and the resulting free fatty acids can then be taken up by local tissues and used as an energy source. Due to the profound effect LpL has on plasma TG and metabolism in general, discovering and developing compounds that affect LpL activity are of great interest.
Metabolic syndrome is a combination of medical disorders that increase one's risk for cardiovascular disease and diabetes. The symptoms, including high blood pressure, high triglycerides, decreased HDL and obesity, tend to appear together in some individuals. It affects a large number of people in a clustered fashion. In some studies, the prevalence in the USA is calculated as being up to 25% of the population. Metabolic syndrome is known under various other names, such as (metabolic) syndrome X, insulin resistance syndrome, Reaven's syndrome or CHAOS. With the high prevalence of cardiovascular disorders and metabolic disorders there remains a need for improved approaches to treat these conditions
The angiopoietins are a family of secreted growth factors. Together with their respective endothelium-specific receptors, the angiopoietins play important roles in angiogenesis. One family member, angiopoietin-like 3 (also known as angiopoietin-like protein 3, ANGPT5, ANGPTL3, or angiopoietin 5), is predominantly expressed in the liver, and is thought to play a role in regulating lipid metabolism (Kaplan et al., J. Lipid Res., 2003, 44, 136-143). Genome-wide association scans (GWAS) surveying the genome for common variants associated with plasma concentrations of HDL, LDL and triglyceride found an association between triglycerides and single-nucleotide polymorphisms (SNPs) near ANGPTL3 (Willer et al., Nature Genetics, 2008, 40(2):161-169). Individuals with homozygous ANGPTL3 loss-of-function mutations present with low levels of all atherogenic plasma lipids and lipoproteins, such as total cholesterol (TC) and TG, low density lipoprotein cholesterol (LDL-C), apoliprotein B (apoB), non-HDL-C, as well as HDL-C (Romeo et al. 2009, J Clin Invest, 119(1):70-79; Musunuru et al. 2010 N Engl J Med, 363:2220-2227; Martin-Campos et al. 2012, Clin Chim Acta, 413:552-555; Minicocci et al. 2012, J Clin Endocrinol Metab, 97:e1266-1275; Noto et al. 2012, Arterioscler Thromb Vasc Biol, 32:805-809; Pisciotta et al. 2012, Circulation Cardiovasc Genet, 5:42-50). This clinical phenotype has been termed familial combined hypolipidemia (FHBL2). Despite reduced secretion of VLDL, subjects with FHBL2 do not have increased hepatic fat content. They also appear to have lower plasma glucose and insulin levels, and importantly, both diabetes and cardiovascular disease appear to be absent from these subjects. No adverse clinical phenotypes have been reported to date (Minicocci et al. 2013, J of Lipid Research, 54:3481-3490). Reduction of ANGPTL3 has been shown to lead to a decrease in TG, cholesterol and LDL levels in animal models (U.S. Ser. No. 13/520,997; PCT Publication WO 2011/085271). Mice deficient in ANGPTL3 have very low plasma triglyceride (TG) and cholesterol levels, while overexpression produces the opposite effects (Koishi et al. 2002; Koster 2005; Fujimoto 2006). Accordingly, the potential role of ANGPTL3 in lipid metabolism makes it an attractive target for therapeutic intervention.
To date, therapeutic strategies to treat cardiometabolic disease by directly targeting ANGPTL3 levels have been limited. ANGPTL3 polypeptide fragments (U.S. Ser. No. 12/128,545), anti-ANGPTL3 antibodies (U.S. Ser. No. 12/001,012) and ANGPTL3 nucleic acid inhibitors including antisense oligonucleotides (U.S. Ser. No. 13/520,997; PCT Publication WO 2011/085271; incorporated by reference herein, in their entirety) have previously been suggested or developed, but none of the compounds directly targeting ANGPTL3 have been approved for treating cardiometabolic disease. Accordingly, there is an unmet need for highly potent and tolerable compounds to inhibit ANGPTL3. The invention disclosed herein relates to the discovery of novel, highly potent inhibitors of ANGPTL3 expression and their use in treatment.